Each of the answers from the Beginnings column can be followed by an answer from the Endings column with a letter added between the two parts. The Endings clues are given in alphabetical order, which suggests that the clues should be solved in Beginnings order. The clues are intentionally quite restrictive, leading to single answers in most cases. The eleven full words are:
- IMP[L]ANTS
- HEX[A]GRAM
- ICE[B]ERG
- FLU[O]RIDE
- OUT[R]AGE
- CAP[T]IONS
- BAY[O]NET
- EVE[R]MORE
- COP[I]LOT
- CUT[E]NESS
- THEM[S]ELVES
The added letters spell out LABOR and TORIES. The empty line left between clues five and six suggests adding a new letter between the two words to form the answer. The only word which fits this pattern is the answer, LABORATORIES.
The similarity of the words used in this puzzle to the two main British political parties, the Labour Party, and the Conservative Party, a.k.a Tories, was accidental. It did occur to me near the end of puzzle construction, but given the difference in spelling, I did not feel it was an issue. Apologies if anybody got caught up in that coincidence.