So who kidnapped Sigma in VLR? Was it necessary?

[Sirlion]

The question is: if Sigma (67 years old self ) was in Dcom warning everybody for 5 days about Radical-6 with Phi, and the storyline of VLR starts in one of the endings after the bomb explodes, followed by the discovery of 22 years old Sigma, returning from the future on April 12 2029, that the world was fubar and his body was part machine (fantastic moment by the way), which was the ending of VLR, who kidnapped Sigma in his car at the beginning of VLR?

I mean, if Sigma is already there in Dcom and has his old self controlling his young body nobody should have kidnapped him in the first place, no? His old self would just enter his body and that's it, no need for "Zero". His young self would simply be sleeping in the elevator at the beginning of VLR not knowing what happens when he awakens.
So what am I missing here?

[Battler Ushiromiya]

Nobody kidnapped Sigma. He was just knocked out and had his future conciousness swap into his past body. Sigma wouldn't naturally go to Dcom. Future Sigma had to.

[Sirlion]

Yes, I'm aware of that. Maybe I wasnt clear (english is no my primary language), Future Sigma had to go to Dcom and that's okay, my question remains, why was he knocked out in his car in VLR? There was no need for that, his future consciousness would simply take over his young body and his young consciousness would be sleeping in the elevator. No point in having that scene in VLR with him in his car and "Zero" putting him to sleep, no?

[Battler Ushiromiya]

So that Sigma in the future could be asleep, and to give Sigma the assumption that he was kidnapped. Think about it: If you were in your car, and the next second you were in an elevator, you wouldn't be thinking "Have I been kidnapped".

[Sirlion]

Okay, makes sense. Even though his old body was asleep and I think the feeling would have been the same with or without knochking him out. Thanks.

[Major Tom]

Don't forget that life-threatening moments are needed to trigger Sigma to jump. Him being knocked out in his car by a person in a cloak with a gasmask was probably a trigger for young Sigma to jump to the body of old Sigma and vice versa. The person who put young Sigma to sleep was most likely Akane.