In this mystery, we see a man (only his hands are visible) getting into a vault using something like a card at each door. He goes to a safe and dials the combination. Then he takes out a CD with the label "Zygonol" and leaves. After the opening music, we see Rohit on the computer, playing a bike game and Suchi is on the couch, reading. Farhan is oiling his bike. Suchi says that they should write a book about CIA. Rohit says,"Haan, par cover pe sirf meri tasveer hogi." Farhan:"Tab to book koi nahi kharidega." Rohit is not at all pleased. Then Suchi asks where Ishaan and Nikki are and the others don't know. So Suchi calls Ishaan. Suchi:"Ishaan...kya hua? You sound so tensed...(Rohit and Farhan come close to her)...WHAT?? Oh no!" Suchi keeps the phone and Rohit and Farhan ask her what the matter is. Suchi:"Guys...Ishaan ke dad...he's gonna get arrested!" Next thing we see is Ishaan sitting on a sofa in their living room, looking totally shocked, his eyes red, and Nikki crying, sitting on a small couch. Suchi, Rohit and Farhan come there. They're all really sorry for Ishaan's father. Suchi hugs and comforts Nikki, trying to make her stop crying. Rohit sits by Ishaan and comforts him verbally. Farhan sits near both Ishaan and Farhan. On asking, Ishaan says that a formula got stolen from Cambala Research Centre. Since his dad alone had the combination of the safe, his dad has been found guilty. He was sacked from the Institute that morning. Ishaan is really upset and says,"They can't do this, yaar. Mujhe dad ka naam clear karna hi hoga." Suchi:"Hum sabko, Ishaan. We're all with you in this." Rohit:"Yes, Ishaan." The five visit Ishaan's dad in his study next. He was typing something on the computer. Suchi asks him how this happened. Ishaan's dad, Dr. Mehra:"Pandra saalon ka kamaya hua naam...sab ek jhatke mein....khatam. Abhi abhi interrogation hui hai aur...police kuchh der mein aake mujhe police station le jaayegi. Enquiry ke liye." Ishaan says they have solved many cases in Cambala...maybe they can help. Dr. Mehra:"Ye case tum logon ke bas mein nahi hai. Par phir bhi tum jaanna chahte ho to batata hoon." Ishaan's dad tells them (shown in flashback) that after 3 years' hard work, a team of scientists (including him) invented a coating. The world's first non-reactive fireproof coating, Zygonol. When any substance was coated with this, it could not be harmed by fire. But the formula got stolen from the safe. Not only was he the only one knowing the combination of the safe, but also it was his ID card that was used to open the doors. Actually, his bag had been stolen couple of days ago. Naturally he is suspected of the theft. No one except him knew the combination...he had not even written it down anywhere, he had merely memorised it. Just then the doorbell rings and Ishaan opens the door. It's the police who take away Dr. Mehra for enquiry. Before leaving, Dr. Mehra gives them a diary containing the numbers of his colleagues, in case the five need any more information. Nikki starts crying again and Rohit puts an arm around her and comforts her.
Back in HQ, the CIA make a list of their suspects. The suspects are the other three scientists who were working on the Zygonol project alongside Dr. Mehra. The three are Dr. Vishal Reddy, Dr. Amit Modi, Dr. Neena Dixit...their drawings were on the board, with the name underneath. Ishaan suspects Dr. Modi especially since he and Dr. Mehra were nominated for President's Award and after this Dr. Modi will definitely get the award. Next we see Ishaan and Rohit in a park, watching Dr. Modi from behind some bushes. Dr. Modi gets a call. He picks it up and tells the man not to keep calling him. Then Ishaan nudges Rohit and Rohit sets off in another direction and comes running towards Dr. Modi from there. Meanwhile, Dr. Modi has put down his towel on a bench and his bench on top of it. Ishaan crawls under the bench and tries to get the cell. Rohit comes jogging to Dr. Modi, intending to distract him. He asks Dr. Modi the time while Ishaan pulls the towel, to make the cell drop on the ground within his reach. When Rohit sees the cell will make a noise when it drops, he realistically sneezes at the exact moment when the cell falls, covering up for Ishaan. He adds some totally realistic coughs, too. Dr. Modi says "God Bless!" and tells him to take care...weather is really bad. Just then Dr. Modi steps on Ishaan's hand (while Ishaan was taking the cell) unknowingly....Ishaan bites his other hand to stop himself from screaming. Rohit sees this and immediately does some quick thinking and asks him to show an exercise involving lifting of feet which he says he had seen the doctor doing the other days. The doctor says it's knee exercise and shows it to Rohit. He has to lift his feet to do this and Ishaan is able to withdraw his hand.Then Ishaan leaves. Rohit says he'll do it...knee exercise...for his elbows (he sure gets muddled!) and quickly leaves, leaving Dr. Modi a bit confused. Back in HQ, Suchi doesn't approve of what they're doing and says that they should check the scene of crime. Ishaan says no one would allow them to enter CRC (Cambala Research Centre). Suchi:"Ya, but this! Stealing other people's phones!" Ishaan:"Wapas kar denge. I just want to see ke jis din chori hui thi uss din Dr. Modi ke phone mein koi special call aaya tha ya nahi. Pass me the phone." Ishaan checks out the call history. Ishaan:"Ye dekho, chori 12 Jan ko hui thi. Dad ne mujhe bola hai ke safe ke memory card se pata chala hai ke chori raat ko exactly 11:37 ko hui thi. And see this....Dr. Modi ne uss raat 11:15 aur 12:16 ko same number par phone kiya tha. Aur ussi number se itne saare missed calls. Aur aaj subah park mein bhi same number se phone aaya tha."
Rohit gets up at this point and says dramatically (with actions and stuff),"One....Boss, kaam hone wala hai. Aur two...Boss, kaam ho gaya hai!" Farhan gives him a friendly knock on the head and Rohit makes as if to hit Farhan back. Farhan goes down the stairs (on which the two were sitting) and Rohit smiles. Suchi takes the cell and sees the number. Suchi:"Yeh to Cambala ka koi local cell number hai." Rohit:"Gimme the phone. Ishaan, apna voice.....(this part wasn't clear) de." Nikki gets the voice whatever-it-is, a small black speaker sort of thing. Rohit dials the cell number using the doctor's cell and the cell rings in an old godown kind of place. A man in a maroon kurta-pyjama picks it up. Man:"Arre kabse phone try kar raha hoon, mera phone kyun nahi utha rahe ho?" Rohit: (in OUTSTANDING imitation of Dr. Modi) "(coughs) Arre, tum itne gusse mein kyun baat kar rahe ho?..." Suchi smiles, Farhan looks at Rohit with admiring eyes. "...Meri tabiat kharab hai." Man:"To aur kya karoon. Kya kahaan tha tumne? Formula....samajh mein nahi aata, kya kahoon main phone pe." Meanwhile, Rohit has connected that voice whatever-it-is to the computer and the others can hear everything. The others crowd around Rohit's chair. Rohit:" (coughs) To hum mil rahe hain na?" Man:"Thik hai. Tum mujhse milne aa jao. Ya...ek kaam karo. Main tumse milne aa jata hoon." Rohit: "Nahin nahin, yahaan bahut khatra hai. Hum kahin aur milte hain. Aaj raat ko, aat baje..." he looks at Suchi for help, Suchi mouths something "...kabaristaan mein. (coughs)" But Suchi definitely hadn't said 'kabristan'.....it shows the others' silent 'Oh no!' kind of actions and expressions. Man:"Cambala kabristan?" Rohit:"Haan....thik aat baje." and Rohit keeps a phone with a long bout of coughing (those coughs sounded totally real!). The others pounce on him as soon as he keeps the phone. Suchi:"Rohit!! I said 'Cafe Ishtaana', not kabristan!! Woh naya coffee house." Rohit:"Uff...ek second, ek second.." he dials the phone again " (apologetically)...busy aa raha hai." Farhan: (exasperated) "Ab iske wajah se kabristan jaana parega." Ishaan:"Guys, Dr. Modi aur kisike beech formula ka discussion...something's up, guys." Nikki:"Ye sab to thik hai, par jab wo aadmi Dr. Modi se kabristan mein nahi milega, to?" Rohit: (grins) "Milenge. Jab Dr. Modi ne bulaya hai...(in Dr. Modi-kind-of-voice) to Dr. Modi hi milenge, beti."
Next....the maroon-kurta-pyjama-man is at the gates of the Cambala Cemetery. He calls on Dr. Modi's cell. The phone rings close by. The man looks up to see Dr. Modi (actually Rohit...in another awesome disguise) on a bench. 'Dr. Modi' waves at him to come in. The man goes to him. Man:"Kya baat hai doctor. Aise andhere mein akele baithe ho." Rohit:"Wo..andhere mein...kabr...(next what he said wasn't clear to me). (coughs) " Man:"Ye tumhare awaaz ko kya hua?" Rohit was speaking in an extra-weak, ill kind of voice. Rohit:"Gala kharab hai. Baith gaya hai. Isliye main bhi baith gaya." Man:"Waise kaafi achchhi jaga chuni hai tumne milne ke liye. Kabristan. Yahan tumhe bhi aasani hogi aur....mujhe bhi." He takes out a GUN and points it at Rohit. Then he pulls Rohit ("Chal mere saath!"). The other four are hiding among graves nearby and look a little tensed as gun is way close to Rohit. Man:"Humare saath gaddaari, haan? Mujhe pata hai doctor ke formula tune hi churaya hai. Formula mujhe dede, warna main tujhe jaan se maar doonga. Wo formula de mujhe!" He holds his gun with both hands and in the process, moves slightly away from Rohit. The other four grab the opportunity and Suchi shoots a pebble using a catapult. The catapult hits the man in his hand, causing him to drop his gun. The man doubles in pain and Rohit, too, takes the opportunity to push him away and run from there. The man nurses his hand and is puzzled to see 'Dr. Modi' disappear so fast ("Ye bud-dha (old man) itni tez kaise bhaag gaya?.......Doctor...DOCTOR RUK JAO!") The man takes his gun and moves around, looking for 'Dr. Modi'. Nikki is alone behind a tree and Rohit comes there, disguise still on. Nikki, not recognising him at first, almost screams out, but Rohit swiftly shushes her and drops beside her, hiding. The man moves around, and passes a tomb behind which Farhan and Suchi are hiding. Then we see Ishaan hiding behind another tomb. The man comes nearby and Ishaan takes out a small black box kind of thing. He presses some buttons on it and throws it at a distance, slightly away from the man. Suddenly, a tune starts coming from the box and the man rushes to it. He picks up the box and is puzzling over it while the five escape from behind him. The man turns to see them running at a distance and runs after them. But he is unable to catch the five, who race away on their bikes.
Back in HQ, Rohit is taking off his disguise while the other four are sittin down close by. Ishaan asks if anyone noted the man's car number. Nikki had...she shows it to him. Ishaan:"Dam cool, hum isey Cambala Transport Office se track kar lenge. But the main thing is...Dr Modi ne formula churaya hai?" Rohit, who has joined them by now, says, "Woh gun-wala bhi yahi keh raha tha." Suchi:"Lekin yeh confirm kaise karein?" Ishaan:"Dr. Modi se." Then we see Ishaan and Farhan racing to a place by a temple. They hide behind the stairs and Ishaan points out a car to Farhan saying it's Dr. Modi's car. After checking tht the coast is clear, they run to he car. Ishaan opens the lock while Farhan keeps a lookout. Ishaan opens the door by the driver and puts his hand in from there to open the door behind it. Farhan gets in and they lock the car up again. Then Dr. Modi and his wife come down the stairs of the temple. Ishaan hides. Dr. Modi's wife takes the bag Dr. Modi was holding and gets in the car, by the driver's seat. Dr. Modi gets into the driver's seat. Dr. Modi's wife keeps the bag, with vegetables in it, in the backseat without looking, which is a good thing, coz Farhan was hiding there. The car leaves. We see the car moving along a road. Dr. Modi's wife:"Kya hua...un logon ne phir phone kiya?" Dr. Modi:"Haan, wo Shamsher ka call main do din se nahin le raha hoon. Unhe lagta hain ke formula maine chori kiya hai aur fasa Dr. Mehra ko diya hai." While the doctor was saying this, Farhan was shown....he controlled s sneeze with great difficulty. Dr. Modi's wife:"Aree, lekin ye to jhoot hai." Dr. Modi:"Haan main jaanta hoon, lekin kya karun....kafi khatarnaak log hain." Dr. Modi's wife:"To aap ko police ko phone karna chahiye." Dr. Modi:"Koi fayda nahin hai. Mujhe na kehne ki dhamki di hai. Ab samajh mein nahin aata hai ki main..." at this point, Farhan, unable to control himself a second time, sneezes and Dr. Modi and his wife jump and look back...Dr. Modi brakes sharply. Farhan sits up and says:"Aapki gari mein lasan (garlic) hai kya?..." (Dr. Modi and his wife look t each other, amazed) "....tabhi...mujhe lasan se allergy hai. Doctor ne bola tha ke lasan na khana na soongna (smell) aur na..." he stops. Dr. Modi and his wife are spellbound with surprise. Next, Farhan is in Dr. Modi's house, hanging his head. Dr. Modi's wife:"To tumne socha ke mere husband...tum bhi..." Dr. Modi:"Arre, isme iska koi kasoor nahi hai. Ishaan ko apne papa ki chinta hai." Farhan:"Magar sir, ye log hain kaun?" Dr. Modi:"Wo aadmi hai...Shamsher Singh. Ek bahut hi khatarnaak mafia group ke liye kaam karta hai. Wo group rivals ke liye companies ke formula churate hain, unke officers ko bribe karke. Mujhe bhi bribe karne ki koshish kiya tha, Zygonol chori karne ka tarika bhi samjha diya tha, par maine mana kar diya. Jab do din pehle chori hui to unhe laga ke maine chori kiya hai. Aur mujhe pata hai ke Dr. Mehra bhi aisa nahin kar sakte hain. He is a good man." Then he tells that he suspects a person in the office. Before telling the name however, he gets his wife out of the way by asking her to get tea. But before he tells the name, the scene changes. Then we see Shamsher reading a letter with invisible writing using a blue torch. It reads:''Mission Deadline 10th December''. In the corner of the paper is THE tattoo (see MYSTERY OF THE TATTOO). He says that time is running out. Then he gets a call from a man who says he has the formula of Zygonol. Before Shamsher Singh can ask too much, the call gets cut.
END OF EPISODE